package oop4;

/**
 * @author oldliu
 * @since 1.0
 */
///圆
public class Circle {
    public static final double PI=3.14;
    private int r;


    public static void printPI(){
        System.out.println("圆周率是"+PI);
    }
    public Circle(int r) {
        this.r = r;
    }

    public double getArea(){
        return PI*r*r;
    }
}
